His novel, which was shortlisted for last year's Booker prize, was hailed by the chair of judges Maya Jaggi for its "stylistic poise and probing intelligence".

"Taking its aesthetic cues from the artful deceptions of Japanese landscape gardening," she said, "it opens up a startling perspective on converging histories, using the feints and twists of fiction to explore its themes of personal and national honour; love and atonement; memory and forgetting; and the disturbing co-existence of cultural refinement and barbarism."

The shadow of the second world war looms over the novel in which Tan recounts the story of a lawyer who seeks solace in a mountain-top garden after surviving a Japanese war camp and becoming involved in the prosecution of Japanese war criminals. Her friendship with a Japanese gardener is threatened by Malaya's recent history and its political breakdown.

"The layering of historical periods is intricate, the descriptions of highland Malaysia are richly evocative, and the characterisation is both dark and compelling," said Jaggi. "Guarding its mysteries until the very end, this is a novel of subtle power and redemptive grace."

Jaggi was joined on the panel for the $30,000 (£20,000) award by the novelists Monique Turond and Vikram Chandi.

Tan joins a roll call of Man Asian prize winners that includes the Chinese writers Bi Feiyu, Su Tong and Jiang Rong, who won the inaugural award in 2007.

• This article was amended on 18 March 2013, because it used "Eng" as if it was Tan Twan Eng's surname. This has been corrected